1. Field of the Invention
The present invention relates to high-density connectors. More specifically, the present invention relates to modular, high-density connectors for use with automatic testing equipment.
2. Description of the Related Art
It is known in the field of automatic testing equipment to use high-density connectors to test, for example, semiconductor die wafers, RAM, and DRAM. In the process of testing the semiconductor die, a mating circuit board must be provided in order to route the connections of the semiconductor die so that the connections are less dense because of the very high density of the connections on the semiconductor die, which may comprise at least 13,000 connections and up to 48,000 connections. In this way, semiconductor dies can be tested to see if they are operating properly. However, the density of the connections on the mating circuit board is still very high.
One known connector used with automatic testing equipment includes a sub-connector that has pogo pins soldered to both sides of a circuit board. The sub-connectors are arranged into an array to form the connector. Pogo pins include a socket, a pin that is partially disposed in the socket, and a spring disposed in the socket that pushes the pin away from the socket. This arrangement of pogo pins allows the pins to travel within the socket. Pogo pins suffer from several drawbacks. First, the pogo pins are relatively long. Because pogo pins are relatively long, it is difficult to design a compact connector. Also, pogo pins are more likely to have impedance discontinuities and to have more attenuation. Second, pogo pins are expensive because of the difficulties in their manufacturing. Third, the total downward force required to engage all of the pogo pins with the mating circuit board is quite large. Fourth, it is difficult to ensure proper impedance matching of the connector. Fifth, pogo pins have a relatively low density.
Another known connector used with automatic testing equipment includes an array of compression contacts that must be compressed from the top and the bottom when the connector is engaged with the mating circuit board. The problem with this connector is that it takes an extremely large downward force to ensure proper connection of the compression contacts with the mating circuit board. The lifetime of this connector includes a relatively low number of mating cycles. Further, the connector must be mated for a fixed time period before proper operation can be ensured.
Each of these known connectors is also not field-replaceable. Because the connector is not field-replaceable, the entire connector must be sent back to the manufacturer to replace and calibrate the connector when the connector is defective, damaged, or malfunctioning. To replace the connector, the connector must be either de-soldered or broken off from the cables attached to the connector. This is a costly and time-consuming process.